As shown in FIG. 1A, electronic circuit breakers 100A according to the prior art that are used for arc fault or ground fault detection, such as Ground Fault Circuit Interrupters (GFCIs) and Combination Arc Fault Circuit Interrupters (CAFCIs) typically include a pigtail wire 102 that is used to connect to a panel board neutral, such as neutral bar. The pigtail wire 102 also connects internally to the electronics of the circuit breaker 100A. In the depicted embodiment, the pigtail wire 102 may have a length of about 13 inches to about 20 inches (about 33 cm to about 51 cm) of 12 AWG wire that is used to connect to the neutral bar on the panel board. Certain electronic circuit breakers 100A may also use mounting features, such as a mounting tab 103, located on the load side of the circuit breaker 100A to help hold the circuit breaker in position on the panel board. During installation, the pigtail wire is unraveled, measured, cut to length, end stripped, the electronic circuit breaker is installed by hooking the mounting tab 103 under a hook of the panel board, and then the pigtail wire 102 is manipulated into place in a neutral bar socket of the neutral bar, and may be held in place with a screw. This is a very labor intensive process.
While most circuit breakers have historically used a pigtail wire 102 to connect to the panel board neutral bar, recently some manufacturers have begun to use a C-clip 104, as shown in FIG. 1B, to connect directly to a neutral bar 130 of the panel board on the underside of the circuit breaker 100B. In this plug-on neutral design, the circuit breaker 100B is pushed directly onto a stab on the line side and also directly onto a panel board neutral bar on the load side.
Existing pigtail neutral designs have a disadvantage of relatively high installation costs when an installer unravels, measures, cuts to length, strips the end of insulation, and then manipulates the pigtail wire 102 to insert the stripped end into a neutral socket of the neutral bar. Some existing C-clip designs, such as shown in FIG. 1B, have the disadvantage that once the electronic circuit breaker is plugged onto the line side stab and neutral bar, there is limited ability to capture the breaker from coming off (becoming unplugged) or moving around.
Accordingly, there is a need for improved methods and apparatus for connecting the circuit breaker neutral to the neutral bar of the panel board.